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ekhemanth
12-17-2004, 07:14 AM
Guys
I wnat to know what is CMOS and TTL. I know both are IC technologies, but what is the differences and which is better?

vikas
12-17-2004, 09:43 AM
For me its not much of a diffrence ...

cmos runs at 0 and 5 V
ttl runs at 0 and 9 v
and you need a max232 to convert b/w them :) .

happy_99
12-17-2004, 10:36 PM
Some info here !

http://www.allaboutcircuits.com/vol_4/chpt_3/11.html

Regds

happy_99

Vivek
12-18-2004, 07:43 AM
cmos runs at 0 and 5 V
ttl runs at 0 and 9 v
and you need a max232 to convert b/w them .


CMOS runs from 3V to 18V (for digital gates).
TTL runs on supplies 4.75V(Minimum) to 5.25V (MAXIMUM).

Most CMOS, HCMOS CPUS now run on 5V or less. (still digital CMOS gates can take 3V to 18V)

MAX232 is used to convert between TTL level signals to RS232 level signals. RS232 ideally runs on 12V levels.
instead of TTL, ofcourse, you can feed in CMOS signals.
but the conversion by MAX232 is not "between" TTL and CMOS.

Please see the link posted by Happy_99. thats nice intro.

cheers!

vikas
12-18-2004, 11:56 AM
Thx for that :) vivek

Was always confused with it :? but had no time to look it up

sumandeep1984
12-19-2004, 09:56 PM
Be cautious while using CMOS logic gates...static charge in your body (esp in winter due to wollen garments) can damage the chips. Always ground your hands while working...and try to avoid contact with the pins as far as possible